Artemisia herba-alba is an important component of Mediterranean dry steppe floras, being widely distributed in arid areas of the Iberian Peninsula and North-West Africa. In this study, we use genetic, cytogenetic and niche modelling tools to investigate the natural history of the species, focusing particularly on the role played by polyploidization to explain current diversity patterns throughout the main distribution range of the plant. Our sequencing data indicate a complex phylogeographical structure showing similar haplotype diversity patterns on both sides of the Strait of Gibraltar and no clear signals of genetic refugia. According to our cytogeographical results, we inferred multiple polyploidization events, which probably took place on the Iberian Peninsula and in North Africa independently. Environmental niche modelling suggested stable potential distributions of A. herba-alba on both sides of the Mediterranean Sea under present and past Last Glacial Maximum conditions, which could be related to the intricate spatial genetic and cytogenetic patterns shown by the species. Finally, environmental modelling comparison among cytotypes revealed that the niche of tetraploids is narrower and nested in that of diploids, a result that could indicate environmental specialization and could potentially explain recurrent establishment success of tetraploids.
Background: Artemisia herba alba is an aromatic species very rich in secondary metabolites that can be used in traditional medicine. The context and purpose of the study: This species suffers from the degradation of its natural habitat. The creation of collections containing diverse ecotypes is important for its preservation. This species contains essential oils which limit the extraction of DNA. The objective of this study is to optimize the DNA extraction and PCR conditions. The method will be used to evaluate the genetic diversity of Artemisia herba alba in the highlands of Western Algeria as a starting point. Results and main findings: The use of different reagents and the modification of the incubation time allow obtaining white and clear DNA. Moreover, the modification of temperature and duration of hybridization results in clearer ISSR profiles. The use of the genetic markers for the analysis of genetic material ISSR, carried out on 12 individuals, indicates that A. herba alba is characterized by a broad genetic polymorphism. Conclusions: This study permits the optimization of protocol of DNA extraction and amplification by PCR for A. herba alba. Large variability was found between the studied individuals for A. herba alba. The developed markers could be used for screening a large collection of individuals. Brief summary: Artemisia herba alba is a popular medicine plant in North Africa. This plant shows a degradation of its natural habitat. It is necessary to constitute a collection in order to reintroduce it in the highlands of North Africa. For this purpose the genetic characterization is obviously important. Nevertheless, no information is available on this species. Moreover, its essential oils limit markedly the DNA extraction. This study aimed the optimization of DNA extraction and PCR conditions. The results showed, by using different reagents and both time and temperature of incubation, a clearer DNA and ISSR markers profiles. This study also revealed a large variability within A. herba alba which could help investigation on a large collection of individuals and therefore select the most efficient ecotypes for re-introduction this species in highlands of Algeria. Nevertheless, these actions require a good knowledge of the genetic diversity of A. herba-alba. There are no information concerning the use of molecular markers for the study of A herba alba genetic variability. This work was interested in the study of intraspecific genetic diversity of A. herba-alba by using inter simple sequence repeat (ISSR-PCR) technique. Material and Methods Presentation of the study area Our study sites known as El-Manseb (Altitude 1326m) are located in the highlands of the South East of the province of Tiaret (001° 48' 40.8'' E, 35° 01' 19.2'' N) in the North West of Algeria. The soil in this area is shallow and rocky or stony part, with generally calcareous-lime nature. Annual rainfall reaches 330mm; the range of temperatures varies between 2.5°C (cold season) and 35°C (warm season). The dry season took places durin...
Bougoutaia, Y., Garcia, S., Garnatje, T., Kaid-Harche, M. & Vallès, J. 2016. Genome size, chromosome number, and rDNA organisation in Algerian populations of Artemisia herba-alba (Asteraceae), a basic plant for animal feeding facing overgrazing erosion. Anales Jard. Bot. Madrid 73(2): e043. Artemisia herba-alba is a largely-distributed and often landscape-dominating taxon in arid areas of the Mediterranean and Irano-Turanian regions. In Algeria, in 2010 its communities covered 10% of the steppe territory, but its populations have been subjected to overgrazing. A karyological study based on 22 populations together with a cytogenetic characterisation of this species has been performed for the first time in Algerian materials, through genome size and chromosome number determination. Fluorescence in situ hybridisation (FISH) was also used to assess the rDNA loci number and distribution in the two ploidy levels detected. The studied accessions are diploid (2n = 2x = 18 chromosomes, 6 populations) or tetraploid (2n = 4x = 36 chromosomes, 15 populations). One population, occupying a more or less central geographic position among the studied area, presented both cytotypes. Genome size reflects well the two ploidy levels, with no evidence of downsizing with polyploidy. The karyotypes are rather symmetric (2A Stebbins' class). FISH analyses detected four signals (2 loci) in diploid and eight signals (4 loci) in tetraploid cytotypes for both ribosomal DNA genes, which present an L-type (linked) organisation, i.e. with loci from both rDNA genes colocalised. The presence of two ploidy levels suggest a genomic dynamism and even a possible differentiation underlying the morphological uniformity and despite the dramatic decrease experienced by this plant in Algeria in terms of surface coverage. Keywords: Anthemideae, Artemisia herba-alba, chromosome number, cytogenetics, fluorescent in situ hybridisation, genome organisation, genome size, karyology, polyploidy, rDNA loci. ResumenBougoutaia, Y., Garcia, S., Garnatje, T., Kaid-Harche, M. & Vallès, J. 2016. Tamaño del genoma, número cromosomático y organización del rDNA en poblaciones argelinas de Artemisia herba-alba (Asteraceae), una planta básica para la alimentación animal en el contexto de la erosión por sobrepastoreo. Anales Jard. Bot. Madrid 73(2): e043. Artemisia herba-alba es un taxon ampliamente distribuido y dominante en el paisaje en áreas áridas de las regiones mediterránea e irano-turania. En Argelia, sus comunidades cubrían en 2010 el 10% de su territorio de estepa, pero sus poblaciones se encuentran sometidas a sobrepastoreo. Se ha llevado a cabo un estudio cariológico basado en 22 poblaciones, se han caracterizado citogenéticamente por primera vez poblaciones argelinas de esta especie y se ha estimado el tamaño del genoma y el número cromosomático, además de la determinación por hibridación in situ fluorescente (FISH) del número y la distribución de los loci del ADN ribosómico en los dos niveles de ploidía. Las accesiones estudiadas son diploides (2n = 2x...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.